In: Biology
Can the exact same sequence of amino acids fold into different tertiary structures?
The teriary structure of proteins are the result of interaction between different amino acids in the peptide and depends on multiple environmental factors such as pH or the presence of reducing agents which would break the disulphide bonds. Also, if there are multiple sites for disulphide bond formation, formation of one disulphide bond could prevent disulphide bond formation between certain other locations. Also, if the pH changes, the ionization on the amino acids also change, thereby affecting the tertiary structure. The shape of the active sites of certain enzymes which have an induced fit or allosteric modulation also change upon substrate binding or binding of the as allosteric activator or inhibitor.
Therefore, it is not only the peptide sequence but multiple environmental factors that determine the tertiary structure of proteins and so the same peptide sequence could exist in different tertiary structure depending on the interactions present.